Gold-195m

Properties and data of the isotope ¹⁹⁵Au.

Content

General data

Name of the isotope:Gold-195m; Au-195mSymbol:¹⁹⁵Au or 19579AuMass number A:195 (= number of nucleons)Atomic number Z:79 (= number of protons)Neutrons N:116Isotopic mass:194.9650379(12) u (atomic weight of Gold-195m)
Excitation energy: 318.58(4) keVNuclide mass:194.9217048 u (calculated nuclear mass without electrons)Mass excess:-32.56699 MeVMass defect:1.658269884 u (per nucleus)Nuclear binding energy:1544.66844733 MeV (per nucleus)
7.92137665 MeV (average binding energy per nucleon)Half-life:30.5(2) sDecay constant λ:0.022726137067539 s^-1Specific activity α:7.054639104275 × 10⁺¹⁹ Bq g^-1
1906659217.3718 Ci g^-1Spin and parity:
(nuclear angular momentum)11/2-

Radioactive Decay

Half-life T_½ = 30.5(2) s respectively 3.05 × 10¹ seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
Iso	¹⁹⁵Au	100 %

Nuclear Isomers

Nuclear isomers or excited states with the activation energy in keV related to the ground state.

Nuclear Isomer	Excitation Energy	Half-life	Spin
¹⁹⁵Au		186.01(6) d	3/2+

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 116) and isobaric (same nucleon number A = 195) with Gold-195m. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

OZ	Isotone N = 116	Isobar A = 195
71	¹⁸⁷Lu
72	¹⁸⁸Hf
73	¹⁸⁹Ta
74	¹⁹⁰W	¹⁹⁵W
75	¹⁹¹Re	¹⁹⁵Re
76	¹⁹²Os	¹⁹⁵Os
77	¹⁹³Ir	¹⁹⁵Ir
78	¹⁹⁴Pt	¹⁹⁵Pt
79	¹⁹⁵Au	¹⁹⁵Au
80	¹⁹⁶Hg	¹⁹⁵Hg
81	¹⁹⁷Tl	¹⁹⁵Tl
82	¹⁹⁸Pb	¹⁹⁵Pb
83	¹⁹⁹Bi	¹⁹⁵Bi
84	²⁰⁰Po	¹⁹⁵Po
85	²⁰¹At	¹⁹⁵At
86	²⁰²Rn	¹⁹⁵Rn
87	²⁰³Fr
88	²⁰⁴Ra
89	²⁰⁵Ac